Mailing address: rua Barão de Ataliba, 125, ap.11, Cambuí. 13024-140. Campinas, SP, Brasil. [email protected] ABSTRAcT Objective: To evaluate the sensitivity and specificity of different protocols for measurement of vertical jump tests for the diagnosis of explosive strength in soccer and volleyball players at puberty. Method: Cross-sectional study population of 110 non-probabilistic young...

PURPOSE We hypothesized that the initial rate (first 40 ms) of unilateral knee extensor torque development during a maximally fast isometric contraction would depend on the subjects' ability for fast neural activation and that it would predict bilateral jumping performance. METHODS Nine males (21.8 +/- 0.9 yr, means +/- SD) performed unilateral fast isometric knee extensions (120 degrees knee...

The purpose of this study was to: a) identify changes in jump height and perceived well-being as indirect markers of fatigue, b) determine the internal and external workloads performed by players, and c) examine the influence of Yo-Yo IR2 on changes in jump height, perceived well-being and internal and external workloads during a tag football tournament. Microtechnology devices combined with he...

This study aimed to analyze neuromuscular variables (vertical jump and torque in external/internal shoulder rotation) in advanced and novice judo athletes, and to identify which neuromuscular variables allow for discrimination between them. Thirty male judo athletes participated in this study: 19 novice and 11 advanced athletes. The judo athletes performed the external/internal shoulder rotatio...

PURPOSE The aim of the study was to longitudinally assess speed and jump performance characteristics of youth football players over a 3 y period. METHODS Two hundred players across five age squads (U12-U16) from an English Football League academy participated. Sprint performance (10 and 30 m) and countermovement jump height were assessed at 6 mo intervals. Pairwise analyses determined the lev...

Expectations may be for both legs to function identically during single- and double-leg vertical jumps. However, several reasons might prevent this from occurring. The goals of this investigation were twofold: assess the presence of side-to-side jump height differences during single-leg jumps in a homogenous group of healthy subjects and determine if those with a jump height asymmetry possessed...

Ruan, M, Zhang, Q, and Wu, X. Acute effects of static stretching of hamstring on performance and anterior cruciate ligament injury risk during stop-jump and cutting tasks in female athletes. J Strength Cond Res 31(5): 1241-1250, 2017-There is limited research investigating antagonist stretch. The purpose of this study was to evaluate the influence of static stretching of hamstrings (SSH) on per...

The jump squat is one of the exercises most frequently used to improve lower body power production, which influences sports performance. However, the traditional determination of the specific workload at which power production is maximized (i.e., optimum power load) is time-consuming and requires one-repetition maximum tests. Therefore, the aim of this study was to verify whether elite athletes...

PURPOSE The authors conducted a study to develop a repeated-effort test for international men's volleyball. The test involved jumping and movement activity that was specific to volleyball, using durations and rest periods that replicated the demands of a match. METHODS A time-motion analysis was performed on a national team and development national team during international matches to determi...